What is a word for a member of elite?

There are approximations, most of them humorous. Depending on the context, you could use:

upper cruster

self-explanatory

Brahmin

(especially in New England): a person usually from an old, respected family who, because of wealth and social position, wields considerable social, economic, and political power, blah-blah-blah.

blueblood

self-explanatory

patrician

(ancient Roman aristocracy)